The binary cubic Laves phases EuPt2, GdPt2, and TmNi2 form extended solid solutions Eu1−xPt2Inx, Gd1−xPt2Inx, and Tm1−xNi2Inx. Samples within these homogeneity ranges have been prepared from the elements by arc-melting on water-cooled copper chills or by induction melting in sealed tantalum tubes and subsequent annealing. The indides were characterized by X-ray powder and single crystal diffraction: MgCu2 type, Fd3̅m, a = 770.68(6) pm, wR2 = 0.0251, 67 F2 values, 6 variables for Eu0.94(3)Pt2In0.06(3), a = 769.16(6) pm, wR2 = 0.0244, 67 F2 values, 6 variables for Eu0.85(2)Pt2In0.15(2), a = 760.12(9) pm, wR2 = 0.0693, 65 F2 values, 6 variables for Gd0.79(5)Pt2In0.21(5), and MgCu4Sn type, F 4̅3m, a=700.27(6) pm, wR2=0.0368, BASF=0.13(2), 175 F2 values, 8 variables for TmNi4In. The platinum and nickel atoms build up three-dimensional networks of corner-sharing Pt4/2 and Ni4/2 tetrahedra. These networks leave larger voids of coordination number 16 that are filled with the rare earth (RE) and the indium atoms. While the thulium and indium atoms are ordered in TmNi4In, one observes mixed RE/In occupancies in Eu0.94(3)Pt2In0.06(3), Eu0.85(2)Pt2In0.15(2), and Gd0.79(5)Pt2In0.21(5)